The invention relates to power transmission belt de-installation tools and more particularly to a belt de-installation tool having a monolithic body and curvilinear surface by which a belt is disengaged from a pulley.
Belt drive systems comprise a significant and widely used form of mechanical power transmission. Generally a belt runs between two or more pulleys or idlers, more particularly a driver and driven pulley and/or an idler or idlers.
In order to efficiently transmit power between the driver and driven pulleys the belt is installed with a predetermined preload or tension. The amount of tension is generally a function of the horsepower and torque requirements of the drive. Increased horsepower or torque requirements will generally require a commensurate increase in the belt tension.
In order to achieve the proper belt tension, one or more of the pulleys is loosened so the shaft or shafts can be moved to allow a slack condition in the belt. Then, the belt is looped over the pulleys. The loosened pulley or pulleys are then pulled or tightened into a predetermined position, resulting in a tension being created in the belt. This process requires the pulley(s) to be mechanically adjusted in order to properly preload the belt.
Belts may be de-installed from pulley systems using the same methods. For systems with an automatic tensioning device or tensioner, the tensioner spring is put into a locked position, and the belt is removed from the tensioner.
For belt systems without a tensioner, the belt is removed from the pulley(s) by loosening a bracket, bolt or similar device.
Another method of de-installing a belt involves use of a tool that extracts the belt from a pulley groove without mechanically adjusting the pulleys. The tool is used adjacent to a pulley. As the pulley is turned the tool stretches the belt while laterally forcing it out of a pulley groove.
Representative of the art is U.S. Pat. No. 4,193,310 (1980) to Boyer et al., which discloses a pulley having a diverging means extending radially and laterally from the rim for engaging and seating the belt on the pulley rim. This invention does not comprise a bearing surface for gradually removing a belt from a pulley.
The prior art device forces a belt to bend over small radius portions of the tool, causing high stress concentrations that damage the belt during de-installation. Further, as the belt is forced out of the groove, high lateral loads damage the sidewalls of the belt. Finally, the transverse motion of the belt as it moves out of the pulley groove may damage the belt ribs.
What is needed is a belt de-installation tool having a monolithic body. What is needed is a belt de-installation tool having a curvilinear body. What is needed is a belt de-installation tool having an extended belt engaging surface. What is needed is a belt de-installation tool having a pulley groove engaging surface. What is needed is a belt de-installation tool having a lip for engaging a pulley groove. What is needed is a belt de-installation tool that is disengageable from a pulley. The present invention meets these needs.
The primary aspect of the invention is to provide a belt de-installation tool having a curvilinear body.
Another aspect of the invention is to provide a belt de-installation tool having a monolithic body.
Another aspect of the invention is to provide a belt de-installation tool having an extended belt engaging surface.
Another aspect of the invention is to provide a belt de-installation tool having a pulley groove engaging surface.
Another aspect of the invention is to provide a belt de-installation tool having a lip for engaging a pulley groove.
Another aspect of the invention is to provide a belt de-installation tool that is disengageable from a pulley.
Other aspects of the invention will be pointed out or made obvious by the following description of the invention and the accompanying drawings.
The invention comprises a belt de-installation tool having a monolithic curvilinear body. The body comprises a pulley engaging surface for engaging a perimeter of a pulley. A sloped arcuate belt engaging surface extends from the pulley engaging surface at a predetermined angle. A curved surface also extends from each end of the tool at a predetermined angle to the belt engaging surface. The tool is placed on a pulley between belt spans. As the pulley is turned the belt rides up on a curved surface of the tool, holding the tool in contact with the pulley. As it rotates, the belt comes into engagement with and gradually tracks across the sloped arcuate belt engaging surface, moving laterally to a pulley plane until it is fully disengaged from the pulley groove by action of the sloped arcuate belt engaging surface.